The invention belongs to lighting engineering, specifically to the design of general purpose LED-based lamps.
General purpose LED-based lamps possess, as a rule, the following basic units and elements: axisymmetric convex light-diffusing envelope, board with light-emitting diodes (LEDs), convective heat exchange radiator, built-in power supply source and adapter plug for connecting to power line, various additional units and elements which can rise efficiency of operation of the lamp.
Maintaining of the operating temperature regime of LEDs and power supply source is one of the most essential issues, whereas their reciprocal thermal influence is one independent problem. In any case, the problem of excessive heat withdrawal is solved by means of convection heat flow and heat radiation from the radiator surface into ambient air. The more powerful is the lamp, the more actual is the problem of quick withdrawal of heat to the heat flow surface into ambient air.
Known is light-emitting diode (LED) containing box-radiator made of dielectric insulating material and possessing surface of convection heat exchange with ambient air; diffuser of LEDs radiation fixed on the box-radiator; board-mounted LEDS; heat conducting element mounted with possibility of heat exchange with LEDs board and with box-radiator; power source of LEDs; and adapter plug (TW 201405067; IPC F21V3/04, published on 1 Feb. 2014).
Defective features of the known solution are that this design makes it difficult to create a high power LED lamp at acceptable dimensions thereof due to insufficient heat withdrawal from LEDs, heat radiation whereof is restricted, on one side, by the air pad under diffuser, and on the other side, by the closed cavity inside the radiator wherein the power supply source is placed which, in turn, is also a heat source. LEDs and power supply source negatively influence each other, whereas the power supply source occurs to be a weak link the operating temperature whereof should be considerable lower than it can be for LEDs.
Other solutions are known, e.g. CN203477931 U, JP539258782 B2, CN 203500894 U, CN203731137 U, whose common feature is presence of LED light radiation diffuser and location of the power supply source within the closed volume of the lamp body, whereas the power supply source is subject to thermal influence from LEDs.
One has to mention availability of an international application PCT/RU 2014/000997 by the author with priority of 26 Dec. 2014 wherein the design of LED is described which contains board of LEDs equipped with heat dissipater the whole surface whereof is a surface of heat flow and thermal radiation.
The solution described in TW 201405067 is chosen as a prototype, as it is the most approximate to the claimed solution in terms of coinciding features.
The technical result of the claimed solution is improving of heat withdrawal from LEDs and power supply source, enhanced produceability and light efficiency of the lamp.
The claimed invention is characterized with the following cumulative features: LED-based lamp having box-radiator coated with dielectric heat-conducting plastic; printed-circuit board with light-emitting diodes; diffuser covering light-emitting diodes; power supply source; and adapter plug characterized in that the box-radiator consists of the first and second part each of them includes combined aluminum section the internal and external surface whereof is coated with dielectric heat-conducting plastic, external walls possesses elongated ends and a flat area of the surface equipped with heat removing cooling fins, whereas these heat removing fins of the first part of box-radiator are oriented towards heat removing fins of the second part of box-radiator and mounted with a gap; LEDs board is mounted on the flat areas of surface of each aluminum section; while elongated ends of the external wall of each aluminum section are connected with adapter plug by means of dielectric heat-conducting plastic, in the material whereof between elongated ends of the external wall a niche is made for placing of the power supply source, the mentioned niche separated from the aluminum section with an air gap.
In one variant, the combined aluminum section contain hollow spaces of elongated shape, while heat removing fins which restrict these spaces will connect the flat area and elongated ends of the aluminum section.
In another variant, the combined aluminum section has one or multiple closed cavities adjacent to the flat area of the section whose walls are heat removing fins.
An important advantage of this claimed LED-based lamp is minimization of dependence of the temperature regime of the power supply source on LEDs temperature, which allows to drastically increase service life of the lamp. This advantage is achieved due to allocation of the power supply source in a niche made of dielectric heat-conducting plastic and separated from the aluminum section by an air gap, and due to significant increase of the area of heat dissipation from the niche surface into the ambient air, in addition to the high heat dissipation from the entire surface of heat removing fins.
The claimed solution is illustrated with the following graphics:
LED-based lamp contains box-radiator 1 coated with dielectric heat-conducting plastic 2; board 3 with light-emitting diodes (LEDs) 4; diffuser 5 covering LEDs 4; power supply source 6; and adapter plug 7. Box-radiator 1 includes the first and second removable parts, each of them containing combined aluminum section 8, external wall 9 whereof has a flat area 10 and elongated ends 11, whereas internal surface of this flat area 10 is equipped with heat removing fins 12. Heat removing fins 12 of the first part of box-radiator 1 are oriented towards heat removing fins of the second part of box-radiator 1. This reciprocal allocation of heat removing fins 12 creates ventilation cavities 18 which ensure through-flow ventilation of box-radiator 1 in one direction. To ensure efficiency of convection heat withdrawal at any position of the lamp between heat removing fins 12 of the first and second parts of box-radiator 1, gap 13 is created which ensures ventilation of box-radiator 1 in the opposite direction, whereas magnitude of gap 13 is chosen depending on the amount of heat emitted by the lamp.
Board 3 of LEDs 4 is mounted on flat areas 10 of external walls 9 of aluminum section 8 of the first and second parts of box-radiator 1. Whereas, elongated ends 11 of external wall 9 of each aluminum section 8 are connected with adapter plug 7 by means of transition elements 17 which are formed from dielectric heat-conducting plastic 2 simultaneously with filling of each of parts of box-radiator 1. Niche 14 for power supply source 6 is created by filling of dielectric heat-conducting plastic 2 and separated from aluminum section 8 by means of air gap 15, thus ensuring independence of the temperature regime of power supply source 6 and drastic increase service life of the lamp. Power supply source 6 is mounted on board 16 which is installed along the axis of box-radiator 1 and provides eclectic connection of adapter plug 7 with board 3 of LEDs 4.
Shown in drawings
Surface of niche 14 with power supply source 6 is surrounded with air gap 15 in such a way that the heat emitted by LEDs 4 practically does not affect operation of power supply source 6 which is mounted on vertically installed board 16 electrically connected with board 3 of LEDs 4 which is installed on the surface of flat area 10 of aluminum sections 8. Electronic components of power supply source 6 are mounted on vertical board 16, whereas a certain part of these components is located in the part of board 16 which is located in adapter plug 7, while suspended large-format components of power supply source 6 are mounted in such a way that they are located in niche 14.
Elongated walls 11 are connected with adapter plug 7 by means of heat-conducting plastic 2, from the material whereof transition elements 17 are formed.
Assembling of this variant of LED-based lamp is performed as follows. On the prepared first half of box-radiator 1 which includes extruded aluminum section 8 coated all round with dielectric heat-conducting plastic 2 and formed from this plastic transition elements 17, half of niche 14, half of fastening element 19 for diffuser 5—board 16 of LEDs 4 is located on flat area 10 of aluminum section 8. Board 16 of power supply source 6 is mounted along the lamp axis in such a way that to ensure its electric connection with board 3 of LEDs and with adapter plug 7. The second half of box-radiator 1 prepared by the above described method is mated with the first half of box-radiator 1. Mating of the described halves of box-radiator 1 is performed by means of adapter plug 7 on cylindrical surface of transition elements 17. Mating of the parts of the box-radiator and LED-based lamp shall be finished by fastening of diffuser 5 on fastening elements 19.
Commercial Availability
The techniques of manufacturing of LED-based lamp elements are broadly known, well assimilated and provided with highly efficient process equipment with various degrees of automation.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/RU2015/000471 | 7/28/2015 | WO | 00 |